Geologic map that depicts the surface geology of Lamar, Red River, Bowie, Delta, and Titus Counties and parts of Fannin, Hunt, Camp, Cass, Hopkins, Franklin, and Morris Counties, Texas. The 6-page booklet indicates geologic formations, abbreviations, and ages.

In the past 100 years, more than 100 names have been used to designate parts or all of the outcropping Midway and Wilcox rocks in the Gulf Coastal Plain; less than half of these names are used currently by Coastal Plain geologists, and the validity of some of the remaining named rock units has be

Geologic map that depicts the surface geology of Rains, Wood, Upshur, Marion, Harrison, Smith, and Gregg Counties and parts of Camp, Cass, Panola, Rusk, Cherokee, Anderson, Henderson, Van Zandt, Hunt, Morris, Franklin, and Hopkins Counties, Texas.

One of the basic mineral resources of Texas is abundant deposits of lignite in Eocene rocks of the Gulf Coastal Plain.